Disproportionation reactions are those in which one element undergoes both oxidation and reduction both simultaneously. In the reaction,
Oxygen in reactant H2O2 is in −1 oxidation state. Oxygen in product H2O is in −2 oxidation state and in other product O2 , it is in 0 oxidation state. So, in this reaction oxygen undergoes oxidation and reductionboth simultaneously. In the reaction,
Chlorine in reactant Cl2 is in 0 oxidation state. Chlorine in product NaCl is in −l oxidation state and in other product NaOCl,Na is in +1 oxidation state, 0 is in −2 oxidation state and Cl is in +1 oxidationstate. So, in this reaction chlorine undergoes oxidation and reduction both simultaneously.